diff options
Diffstat (limited to 'drivers/usb')
| -rw-r--r-- | drivers/usb/dwc3/gadget.c | 26 |
1 files changed, 15 insertions, 11 deletions
diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c index bf2eaa09d73c..0a6633e7edce 100644 --- a/drivers/usb/dwc3/gadget.c +++ b/drivers/usb/dwc3/gadget.c @@ -2984,6 +2984,7 @@ static int dwc3_gadget_init_in_endpoint(struct dwc3_ep *dep) struct dwc3 *dwc = dep->dwc; u32 mdwidth; int size; + int maxpacket; mdwidth = dwc3_mdwidth(dwc); @@ -2996,21 +2997,24 @@ static int dwc3_gadget_init_in_endpoint(struct dwc3_ep *dep) else size = DWC31_GTXFIFOSIZ_TXFDEP(size); - /* FIFO Depth is in MDWDITH bytes. Multiply */ - size *= mdwidth; - /* - * To meet performance requirement, a minimum TxFIFO size of 3x - * MaxPacketSize is recommended for endpoints that support burst and a - * minimum TxFIFO size of 2x MaxPacketSize for endpoints that don't - * support burst. Use those numbers and we can calculate the max packet - * limit as below. + * maxpacket size is determined as part of the following, after assuming + * a mult value of one maxpacket: + * DWC3 revision 280A and prior: + * fifo_size = mult * (max_packet / mdwidth) + 1; + * maxpacket = mdwidth * (fifo_size - 1); + * + * DWC3 revision 290A and onwards: + * fifo_size = mult * ((max_packet + mdwidth)/mdwidth + 1) + 1 + * maxpacket = mdwidth * ((fifo_size - 1) - 1) - mdwidth; */ - if (dwc->maximum_speed >= USB_SPEED_SUPER) - size /= 3; + if (DWC3_VER_IS_PRIOR(DWC3, 290A)) + maxpacket = mdwidth * (size - 1); else - size /= 2; + maxpacket = mdwidth * ((size - 1) - 1) - mdwidth; + /* Functionally, space for one max packet is sufficient */ + size = min_t(int, maxpacket, 1024); usb_ep_set_maxpacket_limit(&dep->endpoint, size); dep->endpoint.max_streams = 16; |